Testing device for voltage and current regulators



Sept. 23, 1952 J. AGIN 2,611,806

TESTING usvms FOR VOLTAGE AND cunnzn'r amupmoas Filed Feb. 25, 1949 3 shins-sheet 1 INVENTOR. JUUUS ABIN BY 2 g Ba AGENT Sept. 23, 1952 J. AGIN TESTING DEVICE FOR VOLTAGE AND CURRENT REGULATORS s Sheets-Sheet 2 Filed Feb. 25, 1949 INVENTOR. JULIUS AGIN BY ff AGENT Sept. 23, 1952 AGlN 2,611,806

TESTING. DEVICE FOR VOLTAGE AND CURRENT REGULATORS Filed Feb. 25, 1949 3 SheetsSheet .5

I INVENTOR,

JULIUS AGIN L3 BY Wq-TKrn AGENT Patented Sept. 23, 1952 UNITED STATES ATENT OFF TESTING DEVICE FOR VOLTAGE AND CURRENT REGULATORS 'Julius Agin, Bergenfield, N. .L, assignor to Patterson 0. Stewart, Bronxville, N. Y.

The present invention relates to testing devices for voltage and current regulators, particularly for the regulators generallyemployed in the electric power systems of automobile engines and the like.

Devices are known for testing the operation of a regulator of this type by testing the performance of the electric system in which the regulator is connected. These known devices, however, are incapable of "being used for testing a regulator independently of the system, as when the regulator is on the shelf of "a dealer.

It is, therefore, the general object of my invention to provide 'a testing device having means for testing the operation of a regulatordiseonnected from any external electrical system.

Another object of the present invention is to provide, in a testing device, means for determining the cut-in voltage, the cut-out reverse current, the maximum voltage and the maximum current of a conventional regulator.

A furtherobject. of this invention is to provide, in a testing device of the character described, meansadapting's'aid device for use with different types of conventional regulators.

Still another object of the invention is to providein a testing device of this character, means for indicating insufficient contact between the contact points of the regulator due, .for. example, to the presence ofi'eontaminating matter.

Yet a further "object or the instant invention is to provide a simple, dependable and portable device incorporating some 'orall of the features set forth above.

'Theioregoing and other objects and features of the invention will become apparent from the following description of certain embodiments thereof, reference being had to the accompanying drawing in which:

Fig.1 isa front view of a testing device according to the invention;

Figs. 2"and 3 are'cirouit'diagrams showing different types of well-known regulators to which the invention is applicable;

Fig. '4 is a circuit diagram of the testing device shown in 1; and

Fig. 5 is a circuit diagram of a somewhat modified testing device according to the invention.

Referring to Fig. l,'there is shown a testing device El ii comprising a casing l I the front part of carries a plurality of manual control and indicator .means. The manual controlm'eans includearotatable-knob 8, a similar knob'9,'a pushbutton t2, a two-position switch It selectively adapting the device for use with one or the other type of regulators subsequently described, the positions of this switch being indicated at L and Y R, and a sequence switch I4 having three positions 1, II and III. The indicator means include the "dials and pointers of a voltmeter It and of an ammeter It, a white lamp [1 and a red lamp E8. The voltmeter dial carries a mark 19, indicating normal cut-in voltage, and a marl; 2 indicating normal maximum voltage; the ammeter dial carries a mark 2!, indicating normal reverse-current cut-out amperage, and a mark 22, indicating normal maximum current. An armature wire 23, a field wire 24, a battery wire 25 and a ground wire -26 extend from the easing H.

Before proceeding with the descriptionof the operation of the device Ill, it will be well to recall the functioning of a conventional voltage and current regulator used in automotive generator systems. Two such generator systems are in concurrent use: In the first, the field winding is permanently connected to the ungroundedterminal of the armature of the generator; in the second, it is so connected to the grounded terminal thereof.

Referring to Fig. 2, there is shown a regulator 27 adapted for use with a generator system of the first type, the generator system being shown in dotted lines. Regulator 27 comprises a cut-in relay 2 8, a current limiting relay 2'9 and a voltage limiting relay 3B. Relay 28 has ahi'gh-resistance winding 28a and a low-resistance winding 28b. The regulator is also provided with an armature terminal 3!, a field terminal 32 and a battery terminal 33, as well as with a ground indicated at 34. A resistor 39 shunts the armatures of relays 2'9 and 30.

The generator system served by the regulator 27 comprises a generator 3'5, having an armature 3t and a field winding 31, and a storage battery 38. 'In operation the armature 36 is connected between ground and terminal 3| of the regulator, the winding 3'! is connected between terminal 32 and the ungrounded armature brush, and the battery 38 is connected between terminal 33 and ground.

At the start, i. e. when the generatoreli begins to rotate, its residual field magnetism produces an output voltage at the armature terminals Which intensifies the field, thereby in turn increasing the generator output. When the cut-in voltage of the regulator is reached, relay 28 operates via its high-resistance winding 28a and closes its contacts, thereby completing a further energizing circuit for itself from terminal 3|, low-resistance winding 2812, relay 2-9, terminal '33, battery 38 to ground. If the battery voltage is lower than the generator voltage, current flows through the Winding 28b in such a sense as to reinforce the action of winding 2811; iii this cur rent becomes too large, relay -29 operates and reduces the field current of generator 35, whereas, if the voltage exceeds a predetermined maximum, relay as operates in parallel with winding 28a with a similar result. Should, however, the

voltage of battery 38 exceed the generator voltage, current flows through the winding 28b in the opposite sense, thus restoring this relay to normal and opening its contacts, thereby disconnecting the battery from the generator, as soon as this reverse current reaches a certain magnitude.

Fig. 3 shows a regulator 21' which is generally similar to regulator 21, comprising a cut-in relay 28', a current limiting relay 23' and a voltage limiting relay 39', as well as armature, field and battery terminals 3!, 32, 33, a ground 34, and a shunt resistor 33. The associated power system comprises a generator 35, with armature 36 and field winding 37', and a battery 33'. Winding 31' is connected between ground and field terminal 32' of the regulator, its energizing circuit being completed over back contacts of relays 29', 30, armature terminal 3! and armature 36'. The operation of this regulator is completely analogous to that of regulator 21 shown in Fig. 2.

Turning now to the operation of the testing device IB, it will be seen that the circuit of Fig. 4 includes the control elements 8, 9, I2, I3 and I4, the indicators I5, IS, IT and I 8, and the conductors 23, 24, 25 and 23 illustrated in Fig. 1. Conductor 23 leads to an armature terminal I31, conductor 25 to a field terminal I32, and conductor 25 to a battery terminal I 33, conductor 26 being grounded at I34. It will be understood that, in operation, terminals I3I, I32 and I33 are connected to terminals SI, 32 and 33, respectively, of a regulator 27 (Fig, 2), or to the corresponding terminals 3I, 32 and 33' of a regulator 27 (Fig. 3).

Fig. 4 shows the three-position switch I4 as a multi-bank switch having six contact arms I4a, I4b, I4c, I4d, Me and I4), each cooperating with three bank contacts representing positions I, II and III. Contacts Ia and 1m of the first bank are connected in parallel to the wiper 48 of a potentiometer representing the control element 3; the lower terminal 45 of this potentiometer is connectedjthrough a resistor 43, to ground I34 via conductor 26, the upper potentiometer terminal being connected through a resistor 44 to contact I3L of the two-position switch I3 which is shown as a double-throw, triple-pole switch. Contact ID is connected to the junction 45 between resistance elements 9 and 43 by way of a resistor 46, and in parallel thereto, through a relay 69, to battery terminal I33 via conductor 25 and ammeter IB shunted by a resistance 54. Contact 1110 is connected by a lead III to the windin of a relay I20, a companion relay II 9 thereof being connected via a lead 6'! to the wiper I4c. Contact IId is connected, over a lead 63, to the upper one of the three armatures of switch 1 3. Contact IIId is connected to a conductor 49 which in turn is connected to the electrical mid-point 4'! of a source of direct current, shown here as a pair of batteries I45, I 43. Contact He is connected via a conductor 48 to the winding of a relay 40 and, thence, to the center armature of switch I3. Contact HR is connected to the lower armature of switch I3 by way of a conductor 64 and a resistor 65. Contact If is connectedto grounded conductor 26 by way of a conductor 62 and white lamp I'I.

Swith arm I 4a is connected to conductor 23 and armature terminal I 3| by way of lead 23. Switch arm I4!) is connected to the lower terminal 56 of the series resistors 43, 9, 44, and to ground at I34 by way of conductor 26. Switch arm I4d is connected through a lead 66 and a resistor 59 to field terminal I32 and also to conductor 48. Switch arm Me is connected via a lead 59 to the winding of a relay 50 and, thence, to the center armature of switch I 3 by way of a tongue and back contact 4i of relay 43. Switch arm I4 is connected to ammeter terminal 5'! and to the winding of relay 60 by way of a conductor 63.

The relay 43 has another tongue and front contact 42 connecting the conductor 29 to ground at I34 by way of the white lamp Ii. Relay 53 similarly connects, over a tongue 5I and a front contact, the red lamp !8 between ground at 34 and conductor 49.

Push-button I2, when actuated, connects a pair of relays 9!], I08 across the batteries I45, 145. Tongues and front contacts IiII, I2I of relays IE3 and I23 are in series, connecting the lower (positive) terminal of battery I43 to terminal I33 through ammeter I6. Tongues and front contacts BI, III of relays and H3 are likewise in series, connecting the upper (negative) terminal of battery I45 to terminal I3! through a rheostat representing the control element 8. Terminal I3I is connected to ground at I34 by way of voltmeter I 5 in series with a resistance 53.

The upper right-hand contact I3R of switch I 3 as well as the lower right-hand contact I3R" are grounded via conductor 23. Center right-hand contact I 3R and lower left-hand contact I3L" are connected to terminal I3I via lead 23. Center left-hand contact I3L is likewise grounded by way of lead 26. Upper left-hand contact I3L, connected to upper resistance terminal 55, is also connected, via contacts SI of relay 90, to the negative terminal of battery I45.

The connections of switch I3, described above, are such that in its left-hand position the apparatus I 0 will be adapted to test a regulator of the type shown in Fig. 2, while in the right-hand position of the switch I3 a regulator of the type shown in Fig. 3 may be tested. Both operations being analogous, it shall be assumed in the following that the switch is in its left-hand position and that regulator 21 of Fig. 2 is connected to the apparatus in the manner previously set forth.

For the first test, determining the cut-in voltage of the regulator, switch I4 is in position I. When the push-button I2 is depressed, relays 39 and I30 operate, closing their respective contacts BI, IEI. The resistance chain 43, 9, 44 is now connected across the batteries I45, I46, and arm Ma applies to the voltmeter I5 a negative voltage which simulates the voltage from the armature 35 of a generator 35. When this voltage reaches a value sufiicient to energize relay 28, upon suitable adjustment of the element 9, relay 28 closes its contacts, thereby completing a low-resistance connection between terminals 3I I3I on one hand and terminals 33, I33 on the other. It will be noted that, in position I of switch I4, resistor 43 is connected in parallel with resistor 43, thereby zeducing the potential of the potentiometer wiper Relay 60 operates in a circuit from ground, arm I4b, conductor 63, ammeter I6, terminals I33, I3I switch arm I4a to potential, and looks at contacts 5| to switch arm I412. Upon closure of contacts 6|, terminals I3I, I33 form, in effect, diagonally opposite junction points of a bridge circuit whose arms are the upper and lower portions of resistance chain 43, 3, 44 (separated by wiper 48) and the batteries I45, I46, owing to the negligible resistance of elements I6, 54 connectin terminal I33 to junction 41. A circuit is thus closed for the ammeter I6 the pointer of which is deflected, the instant of deflection indicating the cutting-in of the regulator. The cut-in is more clearly marked by a lighting of white lamp II which is energized inparallel with relay 68 via switch -arm I4). The reading of voltmeter I5 at. this instant should correspond to thernark Is if the regulator is satisfactory.

The voltage applied between terminals 'I 3I, I 33 is substantially equal in sign and magnitude to the potential diiierence between the wiper '48 of potentiometer Q and the junction point M. At the moment. of cut-in, this potential difierence will generally be of negative polarity, thus corresponding to the case of the generator output being greater than the voltage of battery 33. Knob '9 (Fig. 1) is now rotated backwards (corresponding to a downward movement oi the wiper 48 in Fig. 4) until the current through amm'eter I6 and windings 28b, 29 of the regulator reverses. When this current is sufficiently large, relay 28 releases as previously described; the pointer of ammeter I6 thus returns to neutral, immediately after having reached an extreme reading which should correspond to the mark 2! in Fig, 1.

The sequence switch I4 is now rotated into position II. In this position the aioredescribed circuits for relay G and lamp II are broken at the arms I47), Idf, respectively, the relay lit being unable to hold up in series with resistors 43, 36. The voltage tapped off at the potentiometer 9 is still applied to the voltmeter I5, as well as to armature terminals I3I, 3i, this voltage having been increased by the removal of shunt resistor Rt. Relay 28 operates as before, and the rotation of knob 9 is 'now'continued in a forward direction (corresponding to an upward movement of the wiper 48 in Fig. 4) until the relay 30 operates, opening its back contacts. It will be noted that relay at is connected between field terminal I32 and ground, over contact I3L' of switch I3, and that switch arm Md in position II connects terminal I32 to the high-potential (negative) side of the current source I45, I46 via contacts 9! of relay 9i), switch contact ISL and resistor Normally, the field terminal 32 of the regulator 27 will be grounded via back contacts of relays 2s and 3d, so that the voltage drop across relay 58 will be substantially zero and relay 50 will remain unoperated. As soon, however, as relay it opens its contacts, relay 40 operates, lighting white lamp II via contacts t2 and lead 49. At this instant the reading of voltmeter I5 gives the maximum or operating voltage of the regulator and should correspond to the mark 20.

It is, however, possible that dirt or other causes prevent the contacts of relay 29 and/or 39 from completely closing the circuit between terminal 32 and ground 34 of the regulator. In this event a certain voltage drop will exist between terminal I32 and ground, long before the operation of potentiometer 9 has caused relay 36 to operate. This voltage drop will be insufficient to energize relay 40, which has a high operating voltage, but will be adequate to energize low-voltage relay 5!} connected in parallel with relay It over back contacts II of the latter. Operation of relay 59 lights the red lamp I8, indicating imperfect contact at relay as or So of the regulator. Relay 50 may be slightly slow-operating, as shown, in order to give relay dd time to break its circuit in the normal functioning of the regul'ator.

For the final test the switch It is moved into position III. In this position the relays III], I20 are energized via switch arm Mo and leads 5?,

69, closing contacts III and I2I. Batteries I45, I46 'are now connected between terminals I31 and I33 by way of ammeter It, with its shunt resistance '54, and rheostat 8. The current now flowing through the ammeter is of such polarity as to maintain the relay 28 operated after the same has been energized over its high-resistance winding 28a. This current also passes through relay 29'; when its magnitude has reached a suflicieritly high value, after suitable manipulation of the rheos'ta't 8, relay 29 operates, energizing the relay 4'0 and lighting white lamp I! as in the previous test. The reading of amm'eter It gives the maximum or operating current of the regulator andshould correspond to the mark 22.

In position III or switch I4 the relay 50, associated with red .lamp I8, is connected across terminals I3'I, I33 in parallel with the regulator circuit which includes the front contacts or relay 28. This circuit for relay 5Q may be traced from terminal 'I3I via lead 23, lower left-hand switch contact 13L, resistor 65, lead 64, switch contact III'e, switch arm Me, back contacts 4|, center left-hand switch contact I 3L, contacts IZI, low-resistance amm'eter circuit I6, 54, lead 25 to terminal I33. This time imperfect contact at relay 28 will cause the operation of relay 51 thereby lighting the red lamp I8.

Resistor 65 serves to out down the sensitivity of relay 5B "for the last-mentioned test. This is desirable because of the presence of a certain amount of impedance in parallel with the winding of relay 50, formed by windings-28b, 29 and the ammeter circuit in series, and also because the degree of conductivity at theconta'cts of relay 28 is less critical than at those of relays 29 and 30.

It will thus be seen that the lighting of alarm lamp I8 in position II or III of switch I4 indicates imperfect contact at either or bother the relays 29, 30 or at relay 28, respectively.

In the modification of Fig. 5, all circuit elements corresponding to similar elements in Fig. 4 have been indicated by the same reference numerals.

Switch I5 in Fig. 5 has five banks I ia, I40, Ifld, Me and Hg. The connections of banks I40, Md and Me are identical with those of Fig. 4, except that contact IIId is shown connected to high-voltage terminal 55 in lieu of junction 4?. Relay 6-0 of Fig. 4 has been replaced by three relays Ill, and 160, relay 88 having two windin-gs'80a, 80b.

Switch "arm I la is connected to voltmeter I5 by way of a conductor I23 and to armature terminal I3l over a back contact and tongue II of relay 10. Contacts 'Ia, and IR; are connected, via a conductor I48, to potentiometer wiper 48 as in the previous embodiment.

Switch arm I' lg is connected through a conductor I28, a tongue and front contact SI of relay 80, and the winding of relay ISO to ground lead 26. Contact 19 is connected over a back contact and tongue I I of relay 7B and a conductor I51 to ammeter terminal 51 which latter, in turn, is connectable to ground lead, 25 by contacts I2I, as in Fig. 4. The other arnrneter terminal, 58, which in 'Fig. 4 is directly connected to battery terminal [33, is connected to the same terminal in Fig. 5 through the intermediary of a lead I58 and a back contact and tongue 75 of relay Ill, lead I58 being also connected to tongue 16 of that relay. The front contacts of tongues 74, I5 of relay 10 are connected by lead I4! to junction 41 and also to conductor 49 which connects the tongue 42 to the front contact of tongue I. Conductor I83 leads from the front contact of tongue IE to winding 843a by way of a resistor 83, winding 801) being connected through a conductor I 84 and a resistor 85 to armature terminal I 3i. The energizing circuits for both of these windings include a common lead I'l'I connected to the front contact of tongue H. A conductor I73 connects the front contact of a tongue 73 of relay 79 to a tongue 82 of relay 8d, the latter having a back contact connected directly to one side of white lamp I1 and to one side of red lamp is by way of front contacts and tongues 42, 5I of relays 4i) and to. The other sides of these two lamps are grounded, as in Fig. 4, through a conductor I28. A lead I27 connects tongue St to a tongue ltd of relay I69, the latter having a front contact connected to the front contact of tongue 82.

Adjustable resistors '53, i l take the place of resistors 43, 44 in Fig. 4, thereby dispensing with the need for an auxiliary resistor it controlled by a separate switch arm I421.

The circuit arrangement of Fig. 5 is designed to energize the white lamp I? in position I of switch I4 in such a way that lighting of that lamp will indicate the cut-in of the regulator, as in the previous embodiment, whereas extinction of the lamp I! will indicate the moment of reverse-current cut-out. With this arrangement, the pointer of ammeter I 6 remains deflected so that the magnitude of the cut-off current can be conveniently determined.

Another advantage of the arrangement of Fig. 5 is that any irregularity in the path interconnecting the armature and battery terminals of the regulator, whether the impedance of this path be too high or too low, will be indicated by the lighting of red lamp I8 in lieu of white lamp IT.

The testing device illustrated in Fig. 5 operates as follows:

When the potential difference betwen the potentiometer wiper 48 and grounded terminal 56 has reached such a value as to cause the regulator relay 28 to operate, relay I60 is energized in a circuit which extends from ground at 5t over the Winding of relay I56, lead I28, switch arm No in position I, back contact and tongue it, lead I51, ammeter terminal 51, ammeter I6, ammeter terminal 58, lead I58, back contact and tongue 75, battery terminal I33, the internal circuit of the regulator, armature terminal I31, lead I 23, switch arm la in position I, lead I48 to potential at wiper 5%. Relay I80 closes a circuit for white lamp II extending from ground at 56 over leads 28, I25, lamp I'I, back contact and tongue 82, front contact and tongue I 63, conductor I 4? to potential at junction ll. Belay I53 also closes an energizing circuit for relay Ill extending from negative high-voltage terminal 55 over the winding of relay l8 and tongue ISI of relay I68 to the wiper 48.

The operating voltage of relay I'll is such that this relay will not attract its tongues as long as the potential of wiper 48 corresponds to that at which the regulator normally operates (and which should be more negative than that of junction 17). After the potentiometer has been displaced to a certain extent in the reverse direction (wiper 48 moving downwards in the diaram), the voltage drop across the winding of relay it has been increased sufficiently to cause this relay to function; at this point, however, wiper 48 should still be negative with respect to point 4?. Relay 76 in operating opens the previously traced energizing circuit for relay I68 (which, however, is slightly slow-releasing, as indicated) and closes the two energizing circuits for windings 89a and b. The first of these circuits extends from wiper 48 over arm Ida, tongue and front contact II, conductor I'II, winding 80a, resistor 83, lead I83, front contact and tongue 16, lead I58, ammeter I6, conductor I57, tongue and front contact 14, conductor I 47 to point 47; the second extends from conductor IlI over winding 80!), resistor 84 and lead I84, terminal I3I, internal circuit of the regulator, terminal I 33, lead 25, tongue and front contact 75, conductor It! to point 41. It will be seen that both windings of the relay 80 are thus connected in the diagonal il 48 of the measuring bridge, winding 80:; being connected in series with resistor 83 and the ammeter I5, winding 861) being connected in series with resistor 84 and the regulator.

The windings 80a, 80b are differentially wound so that the relay 80 will not operate if current of the same magnitude flows through both of the aforedescribed circuits. Resistors 83, 8 3 are selected so that the resistances of both of these circuits will be the same if the internal circuit of the regulator between the battery terminal and the armature terminal thereof offers a normal impedance to the passage of current; in this event relay I 66 will release without relay 86 having operated. White lamp II, however, remains lit over an alternative circuit which extends from tongue 82 over front contact and tongue lit to point 2?. Relay 70 has locked to arm Ida over its own tongue I2.

As soon as wiper 58 goes positive with respect to point 2.1, reverse current flows through both windings of relay 8!) and eventually breaks the internal circuit of the regulator. When this occurs, relay 86 becomes unbalanced and attracts its tongues BI, 82, thereby breaking the circuit for lamp IT at tongue 82. The circuit for ammeter I6 remains, however, unalfected and the reverse cut-out current may be read thereon.

Should, however, the internal resistance of the regulator have been inordinarily high or low, relay 38 would have operated after relay It! and would hav prevented the release of relay I60 by closing a holding circuit therefor over its own tongue and front contact 8| as well as tongue and front contact I62 of relay 269. At the same time the circuit of white lamp II would have been broken at tongue 82 and a circuit closed for red lamp I 8 over tongue and front contact I64, front contact and tongue 82, and front contact and tongue I63. It will further be apparent that, if desired, one of the resistors 83, 84 may be made variable for the purpose of rebalancing, in such an event, the relay 80 so as to extinguish the red lamp and re-light the white one, whereupon the reverse current cut-out test can be carried out as previously set forth. It will also be noted that an increase in the magnitude of resistors 83, 84 will diminish the sensitivity of relay 8D.

The tests to be carried out in positions II and III of switch I4 are essentially unaffected by the modification of Fig. 5 and will, therefore, not be described again. It can be seen that relay I68 can be energized in position I only and that, with relays I60 and I0 unoperated, armature terminal I3I is connected to switch arm I 411 and to the voltmeter I 5 via tongue II while battery terminal I33 is connected to ammeter terminal 58 via tongue "I5, thus efiectively producing the conditions of Fig. 4.

While the invention has been described with reference to certain specific" flibofdi'ffie'rit's',.it is to be understood that the same have BZengiVen merely by way of illustration and not ass limitation upon the scope of the invention, the latter on the contrary being capableof numerous modifications and adaptations; V for: erarf pl, the meters and I6 coul-d obviously'bie replaced by suitable calibrations at the controllnlobs 8 and 9.. Many other changes will be readily apparent to those skilled in thear-t, it beinglintendedthat all such changes, adaptations and modifications be embraced within the scopepfthe invention as defined in the objects and in the appended. claims;

1. Adevice for testing avoltage and current regulator of the type-having; at. least, three external connections, comprising; afirst; a. second and a third terminal respectively connectable to said three external--connection s,--a; source of electrical energy,'first circuit 'means connect; ing said source in an energizing circuit across one combination of two of the said terminals, control means in said energizing circuit for varying the output of said source}; current responsive indicator means, a source of current,;-second circuit means connecting--- said indicator means. and said source o'f'current in acontrol circuit across another combinationrof twoof"- the said termi nals, said indicator meansbeinga'dapted-tc de.-' tect a substantial change; in theoutput of saidsource of current, -duetovachangeiintheimpedance of said control 1 circuit,,; and to give: a signal upon such change," of impedance, andmeasuring means connected" to said control means for determining themagnitude-ofthe output of said source of, electrical-energy at the instant of said signal.

2. A device for testing: a voltageand current regulator of the type having external'connections including an armature connection; a field connection, a battery connection and a grounded; connection, comprisingPa-first, asecond and athird terminal respectivelyconnectableto said; armature, field and battery'con'nectionsand further provided with a" grounded fourth terminal, a source of electrical energy, switch means for selectively connecting said? source in a plurality of energizing circuits across certaincombinae; tions of two of the saidterminals control;meansin said energizing circuits: for varying the output of said source,:1currentresponsive indicator means, a source of current,'circuitrmeanscon necting said indicator means and; said-source of: current in at least one control circuitacross another pair of the said terminals, said indicator means being adapted to detect a substantial change in the output of said' source of current, due to a change in the impedanceof said control circuit, and to give a signal upo'nsuch'changeof impedance, and measuring meansconnected to said control means for determining the magnitude of the output of said-source of electrical energy at the instant of'saidsignal. v

3; A device for testing an electrical regulator of the type having'a voltage-responsivecut-in relay and a pair of output connections, interconnectable by contactsof'said'relay, and further having input connections for the energizlation of said relay, comprising a'sou rce of variable voltage, first circuit means for connecting' said source across said input connections, control means for varying said voltage, voltmeter means connected across said source, current responsive indicator means, a source of current, and second circuit means for connecting said source of current and said source ofcurrenaand current indicator means being adapted tofgiv a s1g said energy" to. said nergi ng circuit, 0

' source of current due to said indicator means at i said indicator rnan sb'emg a'dap po sturce orcurrent, mmeter mfe,

creator means canteen-51am said gizing circuit; said iridicaffidfirialiis to signal the'appear'anc'e and ldis pp to the osing; and openingfo fjsaidlcont current flow in said second energizmg' c r whereby the mag'nitiide,o'if,said,v Voltage? sa idi cufr'elit outputattn' fistai'l A f and o eningjm'ay aminetermeans, r

5. device for or" thetypehaving' a frla'yf, .ari energizi for'said relay" and afioperjatin "rcuit' 1' contacts of said relay; comp'r electrical ener y, circuit means for connecting said s arce-across sfaid eneigi'ziiii'g'jjcircuit c 1- trol meaiisffor' applying a variable ort responsi e 'indicattrjnieans and a sour rent connectable m aidjoperatmg' circ contacts, and measuringmeans, connec d controlmeans for determini g said variable port g at the instan,

..-,ad .c.e word n t c m-" 1 m u rent respens ve al rmi r m a -m said; operating circuit and adapted t resiiohdT'tO': rafr a am'se rt f if i i r theimpedanceoi saidoperatingc it'excee a pr et rm ed; valu Weer y m iti -L sure o f sa-idcontacts results in an operationbf said;alarm means. 7 M H are. e mpfi ai l l l regulators wherein; sa'd contacts are break cqn; tacts of said relay, said ind;i cator mea s-comf prising switchv means adapted: to disable said alarm means upon operation of said indicator m ans. v 8."A"'testingdevice for electrical;regulate comprisingasourcei of. current, at; lea$lit output; terminals; first circuit .mcans,,ap,plyin first'portionofitheoutput of; said source ac s first com'binationof two-of said output-term, second circuit means? applying iaseicondj porti of the'output ofsaid'source acrossa secondii o binati'on'of two of'said' output: terminals to cause the flow of a current through a load connected between the last-mentioned terminals, the magnitude of said load current depending upon the impedance of the load, control means for varying the magnitude of said first portion, measuring means connected to said control means for determining said magnitude, and current responsive indicator means connected by said second circuit means to said source and between said second combination of terminals, said indicator means being adapted to detect changes in the magnitude of said load current due to changes in the impedance of an internal circuit of a regulator having terminals connected to respective ones of said output terminals, said internal circuit representing the said load.

9, A testing device according to claim 8, further comprising switching means for selecting different combinations of output terminals.

10. A testing device for electrical regulators, comprising a plurality of output terminals including an armature terminal, a field terminal and a battery terminal all connectable to corresponding input terminals of a regulator to be tested, and

a ground terminal, a source of current, a potentiometer having its input connected across said source, a voltmeter, current responsive indicator means adapted to signal the flow of current therethrough, and a switch operable to connect said indicator means between said armature and battery terminals in series with at least a portion of said source and to connect the output of said potentiometer between said armature and ground terminals, said voltmeter being simultaneously connectable by said switch across the output or" said potentiometer, thereby enabling the voltage at the output of said potentiometer to be read at the instant when a cut-in relay of the regulator, responsive to said voltage, interconnects the armature and battery terminals of the regulator, thus actuating said indicator means.

11. A testing device according to claim 10, comprising circuit means connecting said potentiometer and said source in a bridge circuit adapted to produce a variable current of reversible polarity, said indicator means including an ammeter connectable by said switch in series with the output of said bridge circuit between said armature and battery output terminals, whereby the magnitude of the reverse current necessary to inactivate said cut-in relay may be read on said ammeter.

12. A testing device according to claim 10, comprising current responsive alarm means connectable by said switch between said armature and battery output terminals in circuit with at least a portion of said source, said alarm means being adapted to respond to current from said source whenever the impedance externally present between said armmeter and battery output terminals exceeds a predetermined value substantially less than that at which said indicator means will remain inactive, whereby imperfect closure of the contacts of said cut-in relay may be ascertained.

13. A testing device for electrical regulators, comprising a plurality of output terminals including an armature terminal, a field terminal and a battery terminal all connectable to corresponding input terminals of a regulator to be tested, and a ground terminal, a source of current, a potentiometer, a voltmeter, an ammeter, a rheostat, a switch operable in one position to connect the input of said potentiometer across said source and the output of said potentiometer in parallel with said voltmeter across said armature and ground terminals, said switch being further operable in another position to connect said ammeter, said rheostat and said source in series across said armature and battery terminals, and current responsive indicator means connected in circuit with at least a portion of said source between said field output terminal and one of the remaining output terminals other than said battery terminal, said indicator means being adapted to signal a decrease in current from said source due to the opening of respective contacts of a voltage-responsive relay and of a current-responsive relay of a regulator, energized in said one and said other position of said switch, respectively, whereby the magitude of the output of said source efiective to operate either of said relays may be read on said voltmeter and on said ammeter, respectively.

14. A testing device according to claim 13, comprising current responsive alarm means connectable by said switch, in at least one of said positions thereof, in shunt with said indicator means, said alarm means being adapted to respond to current from said source whenever the impedance externally present between said field output terminal and said one of the remaining output terminals exceeds a predetermined value substantially less than that required for the operation of said indicator means, whereby imperfect closure of the contacts of either of said relays may be ascertained.

15. A testing device according to claim 14 comprising switch means controlled by said indicator means and adapted to disable said alarm means upon operation of said indicator means.

18. A testing device according to claim 15 wherein said indicator means comprise a first relay provided with make and break contacts and first signaling means energizable over said make contacts, said alarm means including a second, more sensitive relay connected in, series with said break contacts and provided with make contacts, and second signaling means energizable over the make contacts of said second relay.

17. A testing device according to claim 13, comprising an additional switch for selectively connecting said indicator means to said armature output terminal and to said ground output terminal, thereby adapting the testing device for use with different types of regulators.

18. A testing device according to claim 13, comprising relay means normally maintaining said switch inoperative and push-button means for operating said relay means to render said switch operative.

JULIUS AGIN.

REFERENCES CITED The following references are of record in the OTHER REFERENCES Dykes Automobile Encyclopedia, by A. L. Dyke, 15th Edition, Goodheart-Wilcox Co., Inc., 1928, pages 403 and 404. 

